A prospective study on pain score with transperineal prostatic gold seed fiducial implantation under local anesthetic alone

Abstract

Background: The purpose of this study was to monitor patient pain score with transperineal prostatic gold seed implantation in the absence of conscious sedation. Methods: All patients who were scheduled for image-guided external beam radiation (IGRT) and referred for gold seed fiducials were eligible to participate. Gold seed implants were performed by two radiation oncologists between December 2007 and April 2008. Patients received only local and deep anesthetic. No patients had prophylactic IV cannulation for the procedure. Three gold seeds were inserted transperineally into the prostate. A visual analogue scale from 0 to 10 was used to assess the pain at baseline, local and deep anesthetic infiltration, with each seed drop, and after the completion of the procedure. Results: A total of 30 patients were accrued to this study. The highest recorded increase in pain score was at the time point of deep local anesthesia, at which the mean pain score was 3.8. The mean pain scores at each seed drop were 0.8 (standard deviation [SD]=1.24), 1 (SD=1.26), and 0.5 (SD=0.90), respectively. All gold seed insertion procedures were well-tolerated, with no patients having significant pain post-procedure, and no significant procedural complications. There were only slight increases in dysuria, urinary frequency, constipation, urinary retention and flatulence in 7 patients -none of which required intervention. Interpretation: Transperineal ultrasound-guided gold seed implantation without conscious sedation is well-tolerated and associated with a low complication rate. It is a convenient outpatient procedure obviating the need for resource intensive postoperative monitoring. IntroductionModern prostate radiotherapy is trending towards higher biological doses. [1][2][3][4] There is a greater need for better accuracy in radiation treatment delivery if toxicities are not to increase. For patients undergoing image-guided external beam prostate radiotherapy (IGRT), gold seed fiducial implantation in the prostate is common. These gold seeds are usually small (typically about 1 × 3 mm) and are chemically inert.Being radio-opaque, gold seeds are easily identified on kilovoltage and megavoltage x-rays. This allows for daily online imaging and position adjustment before treatment. Daily online imaging based on fiducials reduces systematic and random errors, and is superior to offline imaging based on bony anatomy.5-9 As a result, studies have established that with the use of fiducials, clinical target volume and planning target volume margins can be reduced, allowing for more sparing of normal tissues without geographical miss. 9,10The Odette Cancer Centre (OCC) has been using fiducials for prostate radiotherapy since 2001. Initially, conscious sedation with intravenous midazolam and fentanyl was administered to all patients prior to fiducial implantation. This required the patient to remain at the OCC for about 1 hour after the procedure for monitoring in the recovery room before discharge. Furthermore, patients were not permitted...